Inductance coil



. LEIB INDUCTANCE COIL July 23,1925.

Filed April 29, 1924 gvwawtoz AUGUST LEE 1; 5, elf 00m 3515' v WlZ/M Patented July 28, 1925.

nausea STATES FATENT GFE ICE.

AUGUST LEIB, OF BEEILIN, GERMANY, .ASSIGNQR TO GESELLSCHAFT FUR DBAHTLOSE TEITEGRAPHIE 1P3. H., OF BERLIN, GERMANY, A. CORPORATION F GERMANY.

, INDUCTALNCE COIL.

Application filed April 29, 1924. Serial No. 709,818.

To all whom it may concern:

Be it lmown that I, A'ucusr Lure, a citizen of Germany, and residing at Berlin, Germany, have invented new and useful Im-.

provements in an Inductance Coil, of which the following is a specification.

This invention relates to inductance coils such as are used in radio frequency-work.

An object of the invention is to provide an inductance coil, more particularly a fla inductance coil, which is provided with an iron core and which shall have a high selfinductance and minimum iron losses.

This and other objects will be apparent from the following description when considered with the tionally showing the coil winding surrounded by an outside iron band. According to the present induction coil may be of any size,;propor-" tions and dimensions. However this inven-' tion is best adapted to be used wlth flat 00115 such as the pancake type ider web. f iifi etc. The most favourable dimensions 0 coils for radio fre ueniy in a publication by Dr. Meissner entitled, The construction of coils for radio frequency technics and their a plication, which publication may be found in the Year Book or Wireless Telegra by and Telephony on age 57 and the fol owing pages volume 3, 00k 1, year of 1909. A A

Referring to the drawin the flat coil consists of winding S and an lIOI1 C016 B. The winding S may be surrounded by an iron band C. v

The core B is made up of a. strip of very invention the is fully discussed thin sheet iron rolled up into a cylindrical shaped spiral for the least iron losses. The outermost convolution of the spiral may have three adj oined side fingers A A After the core is wound into spiral form and inserted into the coil winding S the fingers A A A, may be bent down so that they restand extend radially on the end of the coil winding S.

' The coil may be provided with the outside iron band C, as in Fig. 3, for attaining the smallest possible reluctance for the magnetic circuitand in that case the fingers A A A may be so dimensionedas'to reach the band C and so close the magnetic circuit.

It will be obvious to those skilled in the art that the self-inductance of the coil canbe controlled by the size, number and position of the fingers A A A It is also obvious that this invention is applicable to other kinds of induction apparatus, such as, for instance, transformers.

Having now described my invention, I

claim:

1. An inductance co1l,compris1ng a spiral,

'very thin, sheet iron core, a windin surrounding the said core, an iron ban rounding the said winding, the said core having very thin sheet iron fingers extending therefrom outwardly to the said band to close the magnetic circuit.

2. A coil comprising a spiral sheet iron core, a winding on said core, an iron band surrounding said windingand, fingers integral with said core extending across the winding and joining said band to close the magnetic circuit.

3. A coil comprising a spiral sheetiron core, a Winding on said core, an iron band surroundin said winding, sheet 'iron fingers extending om'said core of sufiicient length that they may be bent to ap roach said band to vary the reluctance of t e magnetic circuit.

AUGUST LEIB.

sur-' 

